Service Manual

Workman HD Series Page 9 − 39 Hydraulic System
Removal (Fig. 28)
1. Park vehicle on a level surface, raise and support bed
(if installed), shut engine off and engage parking brake.
Remove key from the ignition switch.
2. Read the General Precautions for Removing and
Installing Hydraulic System Components at the begin-
ning of this section.
CAUTION
Before performing any service or repair on hy-
draulic system components, relieve system
pressure to avoid injury from pressurized hy-
draulic oil. Stop the engine, remove key from the
ignition switch, rotate the steering wheel in both
directions, lower the bed onto the bed support
and operate other hydraulic accessories.
NOTE: If vehicle is equipped with High Flow Hydraulics
Kit, label hydraulic hoses for assembly purposes.
3. Thoroughly clean junction of hydraulic hoses and
gear pump fittings. Disconnect hydraulic hoses from
gear pump. Install caps or plugs in hoses and pump fit-
tings to prevent contamination and leakage of hydraulic
oil.
4. Loosen two (2) set screws on the pump hub to allow
pump hub removal from the gear pump shaft.
5. Support gear pump to prevent it from falling during
removal.
6. Remove four (4) flange nuts and flange head screws
that secure pump to mount.
7. Slide gear pump shaft out of pump hub and remove
gear pump from vehicle. Locate and retrieve square key
from the pump shaft.
8. If hydraulic fittings are to be removed from gear
pump, mark fitting orientation to allow correct assembly.
Remove fittings from pump and discard O−rings.
Installation (Fig. 28)
1. If fittings were removed from gear pump, lubricate
and place new O−rings onto fittings. Install fittings into
pump openings using marks made during the removal
process to properly orientate fittings. Tighten fittings
(see Hydraulic Fitting Installation in this chapter).
2. Install square key to the pump shaft. Apply antiseize
lubricant to gear pump shaft.
3. Align pump shaft to pump hub. Slide pump toward the
rear of machine until pump flange holes align with holes
in mount. Take care to not damage the pump coupling.
4. Install four (4) flange head screws and flange nuts to
secure pump to mount. Do not fully tighten fasteners.
5. Tighten both screws (item 23) on the pump hub to se-
cure hub to the pump shaft.
6. Allow coupler assembly to locate pump making sure
that no deflection of coupler components exists. Fully
tighten fasteners to secure pump to mount.
7. Remove plugs from hydraulic hoses and pump fit-
tings. Connect hydraulic hoses to gear pump (see Hy-
draulic Hose and Tube Installation in the General
Information section of this chapter).
IMPORTANT: The hydraulic system used on ve-
hicles with the High Flow Hydraulics Kit use two (2)
separate hydraulic reservoirs and hydraulic fluid
type. Make sure to use correct oil when adding hy-
draulic oil to the hydraulic system.
8. Check oil level in the reservoir(s) and add correct oil
if necessary.
9. Start the engine and operate at idle speed until air is
out of hydraulic system.
10.Stop the engine and recheck oil level in reservoir(s).
Add correct oil if necessary.
Hydraulic
System